Stair-traversing wheelchair apparatus

ABSTRACT

An apparatus adapted to carry a wheelchair comprises a frame having side members between which the wheelchair is mounted which frame members carry adjustable support means for raising and lowering the frame means and the wheelchair mounted therein. The adjustable support means of the apparatus comprises four pairs of jacks which are carried on the frame members with the four pairs of jacks being longitudinally spaced relatively to each other and with the jacks of each pair being transversely spaced relative to each other on the side frame members. Drive means are provided for extending and retracting the jacks with control elements regulating the drive means so that the jacks of each pair can be operated in unison to effect the simultaneous extension or retraction of any selected pair of jacks. In addition, means are provided to propel the apparatus horizontally whereby through the extension and/or retraction of selected pairs of jacks and the propulsion of the apparatus in the horizontal direction, the apparatus can ascend or descend a stair flight.

United States Patent [72] Inventor Robert L. Soileau 2524 Gayosa St., Baton Rouge, La. 70802 [21] Appl. No. 857,471 [22] Filed I Sept. 12, 1969 [45] Patented Ju y 13, 1971 [54] STAIR-TRAVERSING WHEELCHAIR APPARATUS 5 Claims, 13 Drawing Figs.

[52] U.S.Cl. 180/8 A, I 280/528 [51] Int. Cl B62!) 5/02 [50] Field oiSearch 180/8 A; 280/528 [56] Reierences Cited UNITED STATES PATENTS 3,049,364 8/1962 Clay 280/528 X 3,215,446 11/l965 Thackrey 280/528 Primary Examiner-Leo F riaglia Anarney-Cushman, Darby & Cushman ABSTRACT: An apparatus adapted to carry a wheelchaircomprises a frame having side members between which the wheelchair is mounted which frame members carry adjustable support means for raising and lowering the frame means and the wheelchair mounted therein. The adjustable support means of the apparatus comprises four pairs of jacks which are carried on the frame members with the four pairs of jacks being longitudinally spaced relatively to each other and with the jacks of each pair being transversely spaced relative to each other on the side frame members. Drive means are provided for extending and retracting the jacks with control elements regulating the drive means so that the jacks of each pair can be operated in unison to effect the simultaneous extension or retraction of any selected pair of jacks. In addition, means are provided to propel the apparatus horizontally whereby through the extension and/or retraction of selected pairs of jacks and the propulsion of the apparatus in the horizontal direction, the apparatus can ascend or descend a stair flight.

PATENTED JUL I 3 lElTl sum 1 or '4 2 06 55 wax/4a I PATENIEUJUUBIQH 3592.282

SHKET 11, UF 4 INVENTOR fzZ/zfaa ATT( )RNISYJ STAIR-TRAVERSING WHEELCHAIR APPARATUS BRIEF DESCRIPTION OF THE INVENTION In general, the present invention relates to an attachment for a wheelchair which will enable the height of the wheelchair to be adjusted and allow the wheelchair tobe propelled in a horizontal direction regardless of the height of the wheelchair.

A primary object of the present invention is to provide apparatus which can be readily attached to a conventional wheelchair which will enable the chair to ascend or descend steps, stair flights or other obstacles such as curbs while the chair is kept level and stable so as not to jeopardize the operator in the wheelchair.

It is a further object of the present invention to provide an apparatus exhibiting the above characteristics which will permit a person in a wheelchair to elevate himself to the approximate height of a standing person so that the operator will be able to reach medicine cabinets, kitchen cabinets and other items which are located at a height within the reach of aperson able to stand but normally out of reach for a person confined to a wheelchair.

Briefly, the preferred embodiment of the present invention comprises two side frame members which are provided with brackets for securing the frame members to a conventional wheelchair so that the wheels of the wheelchair can be spaced above the ground level and the wheelchair completely supported by the frame members. The frame members are provided with four pairs of hydraulic telescoping jacks with'the pairs of telescoping jacks being longitudinally spaced along the side frame elements at selected intervals with respect to each other so that the chair can ascend and descend stair flights and with the telescoping jacks of each pair being laterally spaced with respect to each other on either side of the wheelchair which is mounted between the side frame members. The frame carries a suitable hydraulic reservoir, a pump and drive means which can either be manual or mechanized such as battery-driven electric motors. Conventional control valves are located intermediate the telescoping jack assemblies and the pump and reservoir to regulate the flow of hydraulic fluid to and from the telescoping jack assemblies to selectively adjust the elevation of the individual pairs of telescoping jacks as required for traversing a flight of stairs or raising the wheelchair to a desired level. In addition, the wheelchair is provided with means for propelling the frame in a horizontal direction such as handcranks which enable the apparatus to be manually propelled through suitable gear trains on the wheels of the frame that are driven by the turning of the handcrank. The above objects and advantages of the present invention will be better understood and other objects and advantages of the present invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view from above of the apparatus of the present invention with a wheelchair mounted therein;

FIG. 2 is a side elevational view of the apparatus of the present invention with a wheelchair mounted therein;

FIG. 3 is a plan view from above of the apparatus of the present invention with a wheelchair mounted therein;

FIG. 4 is a fragmentary view taken substantially along lines 4-4 of FIG. 2 illustrating one of the drive trains for propelling the apparatus;

FIG. 5 is a sectional view of a conventional telescoping jack assembly which can be utilized in the present invention;

FIG. 6 is a schematic view of the hydraulic system of the present invention; and

FIGS. 7 to 13 are diagrammatic views illustrating the manner in which the present invention can be utilized for ascending or descending a stair flight.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings and, in particular, to FIGS. 1 to 3, a conventional wheelchair 20 is shown mounted in-a preferred form of the wheelchair apparatus of the present invention 22. The frame of the apparatus comprises side frame members 24, 26 which are affixed to the wheelchair by pairs of brackets or clamps 28, 30, 32 and 34 which can be readily adjusted to facilitate the attachment or detachment of the frame members 24, 26 from the wheel chair 20. Any type of conventional clamp can be utilized for joining the tubular members of the wheelchair to the frame members 24, 26, such as C-clamps which can be welded to the frame members 24, 26 and provided with bolts or other means for adjusting the distance between the clamp jaws to thereby affix the frame members to thewheelchair.

The side frame members 24, 26 each have four vertically extending telescoping jack assemblies 36, 38, 40, 42 and 36, 38', 42' respectively which are joined together byupper and lower horizontal struts 44 and cross bracing 46. The struts 44 and cross bracing 46 lend needed strength to the side frame members 24, 26 andassure the proper longitudinal spacing between the pairs of jack assemblies (36,36) (38,38') (40,40) and (42, 42'

The longitudinal spacing between the pairs of jack assemblies (36,36) (38,38') (40,40) and (42,42) and the size of the wheels on the jack assemblies can be adapted to fit a stair tread of a-particular width. The standard width of stair treads is 12 inches and, for such a stair tread, 4 inch wheels can be used on' the jack assemblies with the spacing between telescoping jacks 36,36 and 38,38 being 8 inches, the spacing between telescoping jacks 38,38 and 40,40 being 16 inches and the spacing between telescoping jacks 40,40 and 42,42 being 8 inches. It is also contemplated that the spacing between these pairs of jacks could be 6 inches, 16 inches and 6 inches, respectively. The spacing between the two front pairs of telescoping jacks 36,36, 38,38 and the spacing between the two rear pairs of telescoping jack assemblies 40,40, 42,42 must be such that the wheels of these jack assemblies can rest on the same tread and the spacing between the telescoping jack assemblies 38,38 and 40,40 must be such that the distance between the wheels of these jack assemblies is greater than the width of a stair tread. As indicated above, the spacing between the various pairs of telescoping jack assemblies depends on the width of the treads. While the apparatus, as shown, does not illustrate a frame wherein the side frame members 24, 26 can be longitudinally adjusted to adapt the apparatus for treads of different widths, a frame with horizontally extending telescoping struts and suitable cross bracing to permit the selected adjustment of the distance between the pairs of telescoping jack assemblies can be provided for the present invention.

As best shown in FIGS. 2 and 3, a 44 is provided for the reservoir 46, pump 48, motor 50 and battery 52 of the present invention which are utilized to provide pressurized hydraulic fluid to the telescoping jack assemblies 36,36, 38,38, 40,40, and 42,42. Platform 44 is bolted, clamped or otherwise suitably affixed to frame members 54 of the wheelchair so that the platform with the components 46, 48, 50 and 52 mounted thereon can be removed when the apparatus 22 is not in use. The pump 48, motor 50 and battery 52 are all conventional in nature. Therefore, they will not be discussed in detail.

As shown in FIG. 5, one form of telescoping jackassembly which can be used in the present invention comprises an outer cylinder 54 with an inlet-outlet port 56 adjacent its uppermost end and telescoping pistons 58, 60. The pistons 58, 60 are urged by springs 62 and 64, respectively, toward their normally retracted position with an annular flange 66 on cylinder 54 acting as a stop to prevent inlet-outlet port 56.from being covered. The pistonhead 68 of the outer piston 58 is provided with a port 70 to permit the passage of pressurized hydraulic fluid therethrough into or out of the chamber formed between the pistons. With this construction, the pressurized hydraulic fluid supplied .to the assembly can act on the upper surface of the'inner piston 60 to extend the inner piston. While the pressurized hydraulic fluid works on both the upper and lower surfaces of the pistonhead 68 of outer piston 58, due to the the chamber formed between the inner pistons causes the upper piston to be extended. Suitable vents 72, 74 are provided in the bottoms of the telescoping pistons to permit the expulsion of air when the pistons 58, 60 are driven down and attllltlll piston rings 76, 78 are provided to prevent the l t'tlkilu f of liytlmulu; lluid between the pistonheads and the ylinder walla ol the jack assemblies. In addition, plates on the bottoms ul'cylinder 54 and piston 58 are provided with extensions 79,79 which are received in keyways in pistons 58 and 60 to prevent relative rotation between the telescoping memhers.

When one particular form of telescoping jack assembly has been shown, it is to be, understood that other forms of telescoping jack assemblies or'double-acting piston assemblies can be utilized along with appropriate hydraulic systems to effect the extension or retraction of the telescoping jack assemblies. In addition, although the present invention is shown with a motor-driven system for pressurizing the hydraulic fluid,

manual systems can also be used. Furthermore, it is contemplated that entirely mechanical systems utilizing screwjacks or the like can be substituted for the hydraulic system illustrated.

FIG. 6 is a diagrammatic illustration of one form of hydraulic system which can be utilized in the present invention with the telescoping jack assembly of FIG. 5. The hydraulic controls 80 of the apparatus, which are shown mounted on side frame member 24, are illustrated as four separate valve elements 82 each of which has an inlet port 84 leading from a common supply line 86 connected to the pump 48 of the hydraulic system. Each of these valve elements 82 is also provided with an outlet port 88 which communicates with the reservoir through a common return line 90. In addition, each of the valves is provided with an inlet-outlet port 92 which leads through lines 94, 96 to one of the pairs of telescoping hydraulic jack assemblies (36,36) (38,38) (40,40) or (42,42 With this arrangement, the pairs of telescoping jacks can be selectively adjusted or adjusted in unison by the control levers 98 of controls 80 which adjust the valve elements so that the desired telescoping jack assemblies as in communication with the supply line 86 for raising, the return line 90 for lowering, or out of communication with either the supply or return line when the lever is in its normal at rest position to thereby maintain the telescoping jack assemblies at a selected level.

Turning now to FIG. 4, a fragmentary view of the apparatus with a wheelchair therein is shown which illustrates one of the drive and brake assemblies 100 of the attachment. Four of these assemblies 100 are provided to drive the wheels on jack assemblies 36,36 and 38,38 to propel the wheelchair apparatus along and to provide a suitable brake, to maintain the wheelchair and apparatus in a fixed position when desired. Each assembly comprises a square telescoping drive rod 102 having its upper end mounted in a bearing 104 secured to strut 44 and .the lower end mounted in a bearing 106 secured tothe lower end of piston 60 of the jack assembly. Affixed to the lower terminal end of the telescoping rod is a bevel gear 108 which meshes with a bevel gear 110 affixed to the jack wheel. The jack wheel is rotatably mounted on the axle 112 of the jack assembly and the axle l 12 is affixed to the lowermost end of piston 60 so thatthe rotation of the rod 102 causes the jack wheel to rotate and propel the apparatus.

Theupper end of each of the telescoping drive rods 102 is provided with a hinged arm crank 114 which enables the drive rod to be turned by hand. In addition, a notched collar 116 is provided which is affixed to the frame of the wheelchair so that the crank arm can be pivoted down into one of the notches to lock the crank arm in the particular position and prevent rotation of the crank arm, the telescoping rod and jack wheel. This provides a means for preventing the rotation of the jack wheel and maintaining the apparatus in a fixed position when desired or necessitated during the use of the apparatus.

The operation .of the apparatus for ascending or descending a stair flight is shown in FIGS. 7 through 13. The operation of the apparatus will be described in detail for ascending a flight of stairs. However, it is to be understood that essentially the same operation is carried out in reverse when descending a stair flight.

When the wheelchair apparatus 22 approaches the first stair riser, all of the telescoping jack assemblies are actuated to raise the chair to three times the height of the stair riser. The apparatus is then propelled forward by means of the drive trains for the wheels of telescoping jack assemblies 36,36 or 38,38 until the wheels of the jack assemblies 36.36 touch the first stair riser as shown in F IG. 7.

The telescoping jack assembly 36,36 are then retracted until the wheels of these assemblies are raised to the height of the first stair tread. Next, the entire assembly is propelled forward by means of the drive trains associated with jack assemblies 38,38 until the wheels of jack assemblies 38,38 touch the first stair riser as shown in FIG. 8. I

The crank arms of the drive trains for jack assemblies 36,36 are then pivoted down to lock the wheels of jack assemblies 36,36 against movement while the wheels of jack assemblies 38,38 are raised to the height of the first tread. Next, the apparatus is propelled forward by means of the drive trains for telescoping jack assemblies 36,36 until the apparatus reaches the position shown in FIG. 9 wherein the wheels of jack assemblies 36, 36 and 38, 38' rest on the first tread with the wheels of jack assemblies 36,36 in contact with the sv xissr W The wheels of telescoping jack assemblies 38,38 are then locked against rotation while the wheels of telescoping jack assemblies 36,36 are raised to the level of the second tread. The apparatus is then propelled forward by means of the drive trains for the jack assemblies 38,38 until the wheels of jack assemblies 38,38 contact the second riser as shown in FIG. 10 with the wheels of jack assemblies 36,36 resting on the second tread.

.With the wheels of telescoping jack assemblies 36,36 locked against movement, the wheels of telescoping jack assemblies are raised to the height of the second tread after which the apparatus is propelled forward by means of the drive assemblies associated with jack assemblies 36,36 until the wheels of jack assemblies 36, 36 contactthe third riser, the wheels of jack assemblies 40,40 contact the first riser, and the wheels of jack assemblies 38,38 rest on the second tread as shown in FIG. 11.

With the wheels of jack assemblies 38,38 locked against movement, the wheels of jack assemblies 36,36 are raised to the height of the third tread and the wheels of jack assemblies 40,40 are raised to the height of the first tread. The apparatus is then propelled forward by means of the drive trains associated with jack assemblies 38,38 until the wheels of jack assemblies 38, 38 contact the third riser and the wheels of telescoping jack assemblies 42,42 contact the first riser as shown in FIG. 12. In this position, the wheels of telescoping jack assemblies 36,36 and 40,40 rest on the treads respectively.

With the wheels of telescoping jack assemblies 36,36 locked against rotation, the wheels of jack assemblies 38,38 and 42,42 are raised to the height of the third and first treads respectively. Then the apparatus is propelled forward by the drive trains associated with telescoping jack assemblies 36,36 until the wheels of telescoping jack assemblies 36,36 contact the fourth riser and the wheels of telescoping jack assemblies 40,40 contact the second riser as shown in FIG. 13. In this position, the wheels of telescoping jack assemblies 38,38 and 42,42 rest on the third and first treads respectively.

The above outlined operation is continued until the stair flight has been traversed after which the wheels of the telescoping jack assemblies can be retracted above the level of the wheelchair wheels to permit the occupant to propel the apparatus 22 along by means of the wheelchair wheels. Of course, if desired, the telescoping jack assemblies can remain first and third semblies associated with the telescoping and jack assemblies A similar procedure is followed for descending a flight of stairs whereby the jack assemblies are selectively actuated to maintain the wheelchair in a 7 horizontal position while the chair descends the stair flight. Of course, when descending a stair flight, the wheelchair is only initially raised enough to insure that the wheels of the wheelchair do not contact the stairs of the stair flight. v

While the preferred form of the invention has been shown and described, it is to be understood that all suitable modiflca-' tions and equivalents may be resorted to which fall within the scope of the invention.

What I claim is:

1. Wheelchair apparatus for ascending and descending stair flights comprising:

frame means for supporting a wheelchair, said frame means having side frame members between which a wheelchair can be mounted;

adjustable support means for raising and lowering saidframe means, said adjustable support means comprising four pairs of jack means carried by said frame means with said four pairs of jack means being longitudinally spaced relative to each other and with the jack means of each pair being transversely spaced relative to each other and carried on said side frame members; means for actuating the jack means of each pair in unison to 6 I effect the simultaneous extension or retraction of a selected pair of jack means when traversing a stair flight; and

means for propelling said frame means.

2. In the wheelchair apparatus of claim I:

said four pairs of jack means comprising two forward pairs of jack means and two rearward pairs of jack means;

said forward pair of jack means being longitudinally spaced a selected distance relative to each other so that said forward pair of jack means can rest on the same stair tread;

said rearward pair of jack means being longitudinally spaced a selected distance relative to each other so that said rearward pair of jack means can rest on the same stair tread; and

, said forward and rearward pairs being longitudinally spaced 

1. Wheelchair apparatus for ascending and descending stair flights comprising: frame means for supporting a wheelchair, said frame means having side frame members between which a wheelchair can be mounted; adjustable support means for raising and lowering said frame means, said adjustable support means comprising four pairs of jack means carried by said frame means with said four pairs of jack means being longitudinally spaced relative to each other and with the jack means of each pair being transversely spaced relative to each other and carried on said side Frame members; means for actuating the jack means of each pair in unison to effect the simultaneous extension or retraction of a selected pair of jack means when traversing a stair flight; and means for propelling said frame means.
 2. In the wheelchair apparatus of claim 1: said four pairs of jack means comprising two forward pairs of jack means and two rearward pairs of jack means; said forward pair of jack means being longitudinally spaced a selected distance relative to each other so that said forward pair of jack means can rest on the same stair tread; said rearward pair of jack means being longitudinally spaced a selected distance relative to each other so that said rearward pair of jack means can rest on the same stair tread; and said forward and rearward pairs being longitudinally spaced relative to each other a distance greater than either of said selected distances.
 3. In the wheelchair apparatus of claim 1: said jack means comprising telescoping hydraulic jacks.
 4. In the wheelchair apparatus of claim 1: said means for propelling said frame means comprising means for driving wheels of two forward pairs of said jack means.
 5. In the wheelchair apparatus of claim 1: said means for propelling said frame means comprising manual means for driving wheels of two forward pairs of said jack means. 